There is recent increasing demand for high-resolution, high-quality images in various applications. As the resolution and quality of images increase, the amount of information regarding the images also increases.
Accordingly, the storage of image information using existing storage media or transmission of image information using media such as existing broadband circuit lines lead to increasing transmission and storage costs.
High-efficiency video compression techniques may be used for effectively transmitting and storing high-resolution, high-quality image information.
To raise efficiency of image compression, inter prediction and intra prediction are available. The inter prediction predicts pixel values of the current picture by referring to information on other picture, and the intra prediction predicts the correlation between pixels in the same picture.
A variety of methods may apply to make an image the same as its original version for the processing unit of a predicted image, for example, a block. Through this, a decoding apparatus may more precisely decode the image (to be more consistent with the original version), and an encoding apparatus may encode the image to be restored more precisely.